Steam-engine



(No Model.)

. W. N. WILLIS.

STEAMENGINE.

Patented Nov. 20, 1883.

/ V i Ma N. PETER$ PhMB-Lilhugnphar. Washington. 0.17.

UNITED STATES PATENT OFFICE.

WALTER N. wILLIs, or TRAPPE, MARYLAND.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 288,684, dated November 210, 1883.

Application filed March 19, 1883. (No model.)

To all whom it may concern.- Be it known that I, WALTER N. WILLIs, of Trappe, county of Talbot, and State of Maryland, have invented an Improvement in Steam- Engines, of which the following is a specifica' tion.

My invention has reference to steam-engines; and it consists in apeculiar arrangement of crank and connectingrod, whereby the crank-pin is caused to travel any desired path that may be described within the circle described by crank-pin when. rigidly attached to end of crank-arm, as it is 110w used, by continually advancing and receding from crankshaft, as more fully set forth in the following specification and shown in the accompanying drawings. which form part thereof.

Heretofore it has been customary toconnect the connecting-rod, through the agency of crank-pin, to the end of the crank, the said crank-pin being thus'caused to travel ina circle around the shaft as a center. If we may consider the pressure on the piston uniform, the power exerted at any point in the revolution of the crankwill be proportional to aline drawn perpendicular from the center of the crank pin to the center line of piston extended through center of crank-shaft, the said perpendicular line being the leverage, and this varies from nothing to half the stroke of the engine, and when the leverage of the crank 1's smallest the movement of the piston is smallest. Bythis construction the engine is wasteful, and not adapted to turn the crank-shaft at a uniform velocity or uniformpower.

The object of my invention is to overcome almost entirely the above objectionable features, by first varying the distance between crank-pin and center of shaft inversely, with variation of leverage in crank as now used; second, by combining the above (first) with the wedge principle involved in pear-shaped cam constructed about connecting-rod, thus tending to insure a uniform power being ex erted on crank-shaft to turn it, except at the dead-centers.

In the drawings, Figure 1 is a side elevation of an engine embodying my improvement. Fig. 2 is a sectional plan of same on line 00 w,

and Fig. 3 is an elevation of modified means to cause the crank-pin to travel in any desired path that may be traced within a circle.

. D, works.

A is the bed-plate. B is the steam-cylinder. 0 is the cross-head.

D is crank-shaft, and is supported in bearings E, and carries rigidly secured to its end the crank F, having slotf therein, in which the block or roller G slides.

I is a crank-pin, which pivots the block or roller G to the connecting-rod H, which may be provided with the pear-shaped cam 71., ar* ranged about said crank-pin, and in. which a roller, K, pivoted by stud J to the end of shaft As the cross-head reciproeates, the crank-pin I is caused to deviate from a circle, as indicated by dotted lines, and thereby accomplishes the results hereinbefore specified. In place of using the pear-shaped cam, the crank-pin may be made to travel in a groove of any desired shape, as h, in the face of plate H, as shown in Fig. 3.

This device is equally adapted to machinery other than steam-engines, and the connectingrod H may be actuated by the shaft, if desired.

I do not limit myself to the exact construction shown, as it may be modified in various ways without departing from my invention.

I am aware of the patents granted to Rug gles, No.' 157 ,765', of 1874, and Rowe, N 0. 102,323, of 1870, and claim nothing therein shown or "described.

Having now described my invention, what I claim as new, and desireto secure by Letters Patent, is-

1. A reciprocating connecting-rod, in combination with a crank-pin, a crank, a crankshaft, and mechanismto cause crank-pin to travel in any desired path that may be traced within a circle, the transverse or longest axis of said path being in line with the connectingrod when on the dead-centers, substantially as and for the purpose specified.

2. The combination of a connccting-rod, a crank-pin, a crank, a crankshaft, and cam device, substantially as described, to cause said crank-pin to travel in any desired path that may be traced in a circle, the transverse or longest axis of said path being in line with the connecting-rod when on the dead-centers, substantially as and for the purpose specified.

3. The combination of a connecting-rod, a crank-pin, a crank having a guideway, a crankshaft, a block or roller pivoted to crank-pin,

and adapted to slide upon said crank, and a cam to cause said crank-pin to move in any desired path that may be traced within a circle, the transverse or longest axis of said path be ing in line with the connecting-rod when on the dead-centers, substantially as and for the purpose specified.

4. The combination of connecting-rod H, having cam-groove h, crank-pin I, slide G, crank F, guidewayf, shaft D, and roller K, substantially as and for the purpose specified.

'5. The combination of steam-cylinder-B and its piston and piston-rod, cross-head 0, conneeting-rod H, having cam-groove h, crank-pin I, slide G, crank F, having guideway f, shaft D, and roller K, substantially as and for the purpose specified.

6. The combination of a connecting-rod, a crank, a crank-pin, a shaft, and a cam so formed as to cause the crank-pin to move in 20 an elliptical path,in which the longest or transverse aXis is in line with the dead-center points of the said crank, substantially as and for the purpose specified.

In testimony of which invention I hereunto 25 

